Screw-driver bit and finder



July 1 1930. L. F5 MEUNIER I SCREW DRIVER BIT AND FINDER Filed March 8, 1928 1 fijw INVENTOR. lean F Mean/22w in: a

A TTORNEY Patented July 1, 1930 neon iunmvrnn, orecnnvnnann on-r0; Assrenon trd-orrioneo Es e-Icebox COMPANY, NEW YORK,

V i scnnw-nn'rvnn B *A'p ncatioa filed: March s, I

-This invention relates t apparatus-fOr driving screws and similarfastening members and has particular applicationtointerchangeable screw driver bits arranged to be operatedby power means.:.f e

Among-the objects oftheinvention are to provide an improved form of bit and finder assembly therefor to arrangeth'e finder "as-- 'sembly :Eorquick application to and removal from a bit, and in general'to improveprior apparatus of the described type in the inter-o est o'f more efficient and Satisfactory service. The invention provides a particular form of bit and a finder assembly which is ap'plicable to and removable from the bit as a unit and'withoutthe loosening of any part or parts and without the use of anytools.

In order to illustrate the invention one concrete embodiment thereofis shown in the accompanying' drawings, in which: V I

Fig. 1 isa verticalsectional view showing the, bit and finder in assembled'relation and 4 operatively disposed in relation to'a rotary V so member; a. p

Fig;*2-is' a side elevational V ew of the bit shown in Fig 1 but viewed fIOIIl'thG opposite side' Q Figs. 3 and iare transverse sectional views substantially on the] lines 3 3 and H of Fig.2z, i pp p Fig. 5 is a top plan view of the finder assembly apart from the bit; and

Fig. 6 is a vertical sectional view of the finder cylinder before the top of the cylinder is crimped over to hold the guide plate 9.

In the embodiment ofthe invention chosen for the purpose of illustration; the finder as sembly A is shown in Fig. 1 'asmounted upon the screw driver bit'B whose shank portion is detachably secured to a rotative member C.

The member 0 may takethe form ofa spin dle projecting from the transmission case D of any suitable machine the extreme for- Ward end of spindle Giorming a chuck nto which theshank end of spindleB is recelved and held by any suitable means, such as a sleeve 0 ball retainer 0 controlled by a spring pressed The finder assembly. A is arranged to beap plied to and removed from bit B as a unitand Ilar shoulder 10 In nnnnmnnny 192s, se iarnolasaess. preferablyicomprises the finder cylinder 7 tical section inrFig. guide member or washer 9. Finder cylinder 7 has a long counterbore providing an annushown by itself in verhasia second and shallower counterbore receivmgguidewmember 9 and providing a shoulder 11 against which guide 9 is clamped by crimping or riveting over the outer end of the findercylinder 7 after spring 8 and guide 9 are disposed withinv the first and second counterbores respectively. The three elements thus: permanentlyunited. Assembly A'is arranged for telescoping engagement with the bit by providing guide member 9 witha perforationor opening in line with the open end 'ofcylinder This opening in. the guide member is such as to cooperate with the conagainst which the lower'end of sprlng 8 seats and the upper end of the finder COIIIPIISiDgetlIQ finder assembly. are

6, a coil spring Send a I tour or form of the shank of the bit intermediate that: portion of the bit which is received within the chuck and that portion which is normallye 'enolosed by the 'finderassembly In the present instance theopening in the guide member 9 is polygonal, having a plu rality ofpointed corners '12 and a-fiat corner 13.1;1Bit B has'a portion'shown' in cross sec tiongin Fig; 4: conformingin all .respectsto the opening i'n guide members to permit the latter toktelescope thereover; =Thus thebit provides three sharp corners, 12%, and a fiat working endthereof to provide a shoulderl, which isengagedb'yithe outer end of spring 8 of (.the finder assembly when the; latter-is mounted uponthelbit (Fig. 1'). Beyondthe corner, 13%. Theykbit; is reduced toward the i 7 1243513 portion of'thebittowardtheshank I 7 end, 'thebitissomewhatreducedgin size by removing the sharp corners (Fig 3). and pro viding -:a second longitudinal flat; surface '15, 1 Therebeyond-hbitB has an annular recess or groovelfi positioned so as to be at least-partly covered by the chuck of the rotatable spindle i whenthe bitf'is inposition' for use (Fig; 1

assembly is 1l1 In:applyingtheffinder assembly A 'to the e bit 13; the :guide member-9 ofthe telescoped over the 125,13? portion of thebit and the telescoping movement is continued ite,

, with a consequent compression of spring 8 until guide member 9 is disposed in the plane of groove 16. 'Since this groove is of greater width than guide 9, the latter together with the entire finder assembly A may be rotated or 'angularly adjusted relative to hit B. When the second flat 15 of bit is diametrically opposite the flat 13, as shown, the finder as: sembly is rotated one-half turn or 180. This brings the flat 13 of guide 9 opposite the sharp corner projection 12 at the base of fiat 15 (Fig. 2), thus interlocking the, finder assembly with the bit and preventing their disengagement. To remove the assembly the 7 previous operation is reversed, the assembly being forced back until guide 9 registers with groove 16, the assembly is givena half turn and can then he slid oif thebit. I Y From the above, it will be apparent: that the present invention provides improved andcooperatingforms of bit and finder'assembly, that the finder assembly is conveniently applied to or removed from the bit withoutloos- I eningany of the parts of theassembly and Without the use of any tools, and that acci dental disengagement of the finder assembly from the bit is prevented when the bit is in operative position within the chuck of a spindle for rotating the same.

While the invention has been disclosed herein in what is now considered to be itspreferred form, it is to be understood that the invention is not limited to the specific details thereof, but covers all changes, modifications and adaptations within the scope of the appended claims.

I claim as my invention a 1. The combination with a rotatable member having a chuck, of a bit adapted to engage said chuck, and a finder assembly on said bit, means including a reduced portion on said bit permitting relative rotation of said assembly and its removal as a unit from said bit, said portion being so positioned as to be when said bit is'operably therefor, said assembly having a guide plate having a polygonal opening there through with a plurality of sharp corners and at least one flat corner,said'bit having a por tionconforming to said opening 'slidably to plate, and an annular groove beyond said portion of a size to receive said guide plate and permit rotation thereof relative to said bit thereby to dispose the flat corner of said plate above a sharp corner or projection on said bit thereb to eifect an interlocking engagement of sai assembly with said portion.

4:. A bit arran 'ed for interlocking engagement with a readily detachable finder assembly, said-bit having a portion polygonal in cross section and providing a plurality of sharp corners and one flat corner, the shank of said Jbit beyond said portion being provided with two flat corners and with an annular groove in said shank portion.

5. A bit arranged for interlocking engagement with a finder assembly, said bit having a portion polygonal in cross section and providing a plurality of sharpcorners and one flat corner, the shank of said bit beyond said portion being provided with opposed flat corners. i and with an annular groove in said shank portion.

6. A keeper assembly for a screw driver bit having a polygonal shank and radial projections adjacent the blade end thereof, said assembly comprising-a keeper cylinder having an internal shoulder, a coil spring within said cylinder and engaging said shoulder, and a guide plate across the end of said cylinder receivesaid assembly and guide plate, and

means on said bit beyond said portionper mitting rotation of'said assembly to dispose said fiat corner above a sharp corner orprojection on said bit thereby to prevent disengagement of said assembly from said bit.

3. In a combination, a bit and a finder as-i isembly therefor, said assembly having a guide plate having a polygonal, opening therethrough with a'plurality of'sha'rp cor ners and at least one fiaticorner, said bit hav ing -a portion conforming; to said opening slidably to receivesaid assembly and guide 

